Quarterly report pursuant to Section 13 or 15(d)

Share-Based Payments - Non-employee Director Non-vested Shares (Details)

v3.7.0.1
Share-Based Payments - Non-employee Director Non-vested Shares (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Non-Employee Director Shares, Vesting Period (in years)     1 year  
Share-based compensation expense $ 2,064 $ 2,159 $ 4,026 $ 4,111
Nonemployee Director Nonvested Shares Granted Member        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Outstanding and non-vested, beginning of period (in shares) 16   16  
Grants in Period 10   10  
Shares Vested in Period (16)   (16)  
Outstanding and non-vested, end of period (in shares) 10   10  
Outstanding and non-vested, weighted-average grant date fair value, beginning of period $ 44   $ 44  
Grants in Period, Weighted Average Grant Date Fair Value 51   51  
Vested in Period, Weighed-average grant date fair value 44   44  
Outstanding and non-vested, weighted-average grant date fair value, end of period $ 51   $ 51  
Outstanding and non-vested, aggregate grant date fair value $ 516   $ 516  
Share-based compensation expense 146 211 317 382
Tax benefit related to share-based expense 53 65 115 135
Unrecognized share-based compensation, net of estimated forfeitures $ 442 $ 592 $ 442 $ 592
Weighted average period over which unrecognized compensation will be recognized (years) 10 months 11 days   10 months 11 days